^^oh maybe my use of the word "market" made it sound like i was talking in terms of sales but that was not at all my intention (although one cant deny that their finantial success is also something to praise too ).
what i wanted to express by saying that their work was remarkable is that they pushed the trends in a new unexplored direction no one had yet dared to experiment with. (call it tacky or rich bitch or whatever it was called then)
in a very different level, OF COURSE, it would be like saying that Saint Laurents transparent blouse was remarkable. that was a new boundary he pushed and not by his well known skills as a designer/crafter/artist. he just had the idea to put together two things that had never been... a blouse (relatively basic cut with no need of gallianesque skills of construction), and transparent fabric... and the result was a huge shock! boom!
so in a way Dolce & Gabbana did also succeed because of their daring attitude: they convinced people that their clothes was the right thing to wear at the moment.
When you ask if H&M (and i guess you'll agree others like Zara or Topshop could be included) should be "raised to the group", i say the only reason why they shouldnt is probably because one can not really say they work with their own ideas (other than the "revolutionary" idea of taking big-names pieces and copying them for the mass market). However, they also need to be greatly considered in the way they may have influenced the high end brands... for some years, specially when every look that went down a runway seemed to be replicated (in Zara, but also in Canal street), i had the impression that the designers where embellishing everything more and more so that they got this unique look and finishing that no zara or chinese workshop could ever replicate. maybe that was just me, but i dont think any major designer can just ignore what's going on in the streets, and the streets nowadays are full of H&M.
I am a business major and i think the economic side of the fashion industry is fascinating. However, as you very well said, if it was because of how much money it makes, i'd be looking at the stock exchange (which I do, but not as frequently as i visit tFS )
what i like about the business side of fashion is that the markets ultimately represent what people like, and what they dont...
and maybe the critics may not praise Pilati's work one season, but if the sales go up, that'll mean he has proved them all wrong because he has the support of people in the streets.
in other times a collection like this winter's Prada lace stravaganza would have seemed absolutely inadequate... but if people have bought it now, maybe it means that she got something right, no? maybe she was feeling something no one noticed before her... and that sure showed up in her bottom line.
i dont think "the numbers" is the most important side of fashion, but one cant underestimate them, never!

JUST A COUPLE OF PS:
1, i wanted to make sure it doesnt look like i am comparing Saint Laurent's talent with D&G's let's say... "skills"! i am soooo not!!
2, that made quite a long post... i need to learn how to simplify...